A141250 - OEIS

%I #4 Nov 25 2014 12:38:51

%S 11,17,23,37,41,97,101,121,137,157,191,211,223,227,331,347,431,443,457

%N Prime powers related to minimal visibility in the square n X n lattice.

%C So far 121 is the only composite here. The numbers in A141249 greater than 1 are 2*a(n)-1.

%Y Cf. A141246.

%K nonn

%O 1,1

%A _T. D. Noe_, Jun 17 2008